1. Field of the Invention
The present invention relates generally to switchgear modules and configurations thereof for the field of electrical power distribution and the method of fabrication and assembly thereof, and more particularly to switchgear modules having improved bus interconnection features and integrally provided features that are formed during molding of the switchgear module and portions thereof.
2. Description of the Related Art
Switchgear are generally categorized by their installation location (e.g. grade or surface, sub-surface etc.), the configuration of components (e.g. loadbreak switches, fuses, interrupters, disconnects, sectionalizers, etc.), the cable connections (e.g. elbows, cable terminators), the accessibility of components, the medium within the switchgear enclosure, for example air, vacuum, oil, gas (such as SF.sub.6), etc., and additional features such as fault indicators, voltage indicators, power operation, automatic fault interruption control, etc. For example, switchgear that incorporate the combination of a vacuum interrupter with a series connected visible disconnect is disclosed in U.S. Pat. 4,484,046 and illustrated in the Square D Bulletin SY-9T (Sep. 1986). In the arrangement of the aforementioned U.S. Pat. No. 4,484,046, the visible disconnect is also connected to a ground when moved to the opened position. Another arrangement, Type RGC switchgear available from ABB and illustrated in Catalog publication N-H 5194 E, utilizes a loadbreak switch and series connected disconnect that is visible and connected to ground in an open position, the loadbreak switch and the disconnect being disposed in an SF.sub.6 environment.
The termination of power cables and the connection of bus structures is also an important aspect of switchgear and its use. An example of a cable connection arrangement that utilizes a junction pad as part of a module that terminates a cable is shown in U.S. Pat. No. 3,597,527. In this arrangement, one module is used to terminate each cable and cable joints or splices are formed by a connecting bolt placed through the aligned junction pads which are biased together, the termination then being completed by the affixing of gaskets and end plates over the exteriors of the junction pads. This arrangement is also shown in G&W Electric Co. Catalog CA2-88 (Mar. 1988). An example of connections between switchgear modules or transformer units is shown in U.S. Pat. No. 5,257,161 including cover guards and conductive tabs on contactors within the cover guards that are provided from each sealed housing, and an insulating mount that is inserted into two facing cover guards of two adjacent switchgear modules, the insulating mount being provided with conductive parts that are shaped and include resiliency so as to form connections with the conductive tabs when assembled between adjacent switchgear modules.
While the prior art arrangements may be useful to provide switchgear of various configurations, the prior arrangements are rather complicated regarding assembly and limited regarding installation and configuration into different arrangements.